Re: "Concave mirror" (was Re: No Subject)

Bob Madden (madden@netcom.com)
Mon, 24 Jul 1995 22:26:58 -0700 (PDT)

Mike I'm inclined to disagree with you as many spherical mirrors have been made, used and with success. Fast sphericals without corrector plates or optics will produce lots of coma, but if it has a long focal ratio, maybe it isn't so bad. Maybe a comment from Mel Bartels or Bratislav Curcic, Peter Hirtle, Rich Combs or any of the other "pro's" could clearify this.

Friendly Bob

):-{])) <---- madden@netcom.com madden@svpal.org Remember amateur astronomers: "keep looking for the next Universe"

On Mon, 24 Jul 1995 MbWanderer@aol.com wrote:

> Hi!
>
> I think what the person who sold you that mirror meant was that the mirror
> was not a paraboloid. A paraboloid is the shape needed to construct and
> newtonian reflector, the only kind of telescope that most amateurs can build.
> And, it probably isn't accurate enough to get you a good image. Too bad, I
> hope you didn't pay a lot for it! Sounds like you might have the makings of
> a small solar furnace, tho.
>
> Good luck!
>
> Mb (Mike Bagneski)
>